Focus finds only a few stars

Hi,

I thought I’ll post my current dilemma here also and not just on Cloudy Nights. Since changing from AT115 to ATRC8 my SG Pro autofocus sequence finds most of the time only a few stars, even when there clearly is tens if not hundreds of them visible of the screen. Needless to say that this significantly affects to focus results (adding one more star to the average of three versus to hundreds), most of the time creating just a zig-zag pattern. I’m not sure if my problem is the scope (first time using a RC), ASI drivers or what but like said, I wanted to share this issue here also in case someone else has experienced similar absurd behavior and would be able to help me.

Thanks,

Mikko

I should have mentioned that I saw and read a few similar posts regarding this issue but didn’t really find anything which would have helped me. Like others, I also have tried different binning, star size, exposure time, etc. combinations with a very little difference to the end result.

  • Mikko

Here’s an example of what I’m talking about.

  • Mikko

Generally longer exposure should help. But if you’re running a very narrow FOV there will likely be certain areas where auto focus won’t work and you’ll need to slew off to a more “star rich” area.

Thanks,
Jared

Thanks Jared. I’m going to double the exposure time to 20 sec and see what that does. I was also thinking that if nothing else, I can probably just focus with Lum filter as these Astrodon’s are quite parafocal.

  • Mikko